Cleansing agents



Patented Nov. 21, 1933 UNITED STATES PATENT orrlcs CLEANSING AGENTSRhine,

No Drawing.

No. 470,787, and in Application Jnly25, 1980, Serial Germany April 23,1930 2 Claims. (Cl. 87-5) During recent years use has been made to anincreasing extent of trisodium phosphate alone or in mixture with soda.in a 2 to 5% aqueous solution, as cleansing and scavening agent for 5industrial and domestic purposes, more especially when it is a questionof the removal of greasy impurities. As is known however, these stronglyalkaline salt solutions very readily attack metals such as aluminium,zinc and tin, and give off hydrogen. For some time therefore suchproducts have not been willingly adopted in Germany for the purposereferred to.

Attempts have been made to find a universal cleansing agent, whichallows of-also cleaning articles made of these metals or metal parts,without ailecting them at the same time. For this purpose it has alreadybeen proposed to treat trisodium phosphatesoda mixtures with waterglass, but such mixtures have also not been entirely satisfactory.

It has been observed in an unforseen manner that an addition ofaluminium sulphate, preferably in quantities of 15 to 20% to trisodiumphosphate or a mixture of trisodium phosphate and soda renders metalssuch as aluminium, zinc or tin practically unaffected by these alkalinesalt solutions. Such a mixture thus represents a cleansing agent whichis uniformly satisfactory for all purposes.

What I'claim' is:

1. A composition for cleaning articles made of aluminium, zinc and tin,consisting of trisodium phosphate, and, for the purpose of preventingcorrosion of the metal article by the said phosphate, 15-20% ofaluminium sulphate.

2. A composition for cleaning articles made of aluminium, zinc and tin,consisting of trisodium phosphate and sodium carbonate, and, for thepurpose of preventing corrosion of the metal article by the saidphosphate and carbonate, 15-20% of aluminium sulphate.

FRITZ DRAISBACH.

